In general, there have been developed video encryption techniques for playing a video, such as encryption methods using encryption techniques, such as the Data Encryption Standard (EES) and the Advanced Encryption Standard (AES) for digital videos, and methods of encrypting specific information of encoded videos, from the scrambling scheme of analog TV.
In conventional digital video encryption methods, a method of encrypting compressed videos rather than a method of encrypting raw video data is performed. This is because raw video data is problematic in that it has a very large amount of data and has low compression performance when the raw video data is modified.
However, in the case where encryption for compressed video is performed, there is a problem in that a transcoding executor must be able to perform encryption and decryption before and after transcoding is performed in order to perform the transcoding.